1. Field of the Invention
The present invention relates to technologies for allowing a user (e.g., network administrator) to manage the Internet or other networks using a graphic screen of a computer (e.g., network management station) provided at one place, particularly to a mechanism for selectively registering a network element as an object to be monitored. A node, a link, a label switched path (LSP), or the like can be the network element.
2. Background
As networks are becoming large-scale and complex, and as end users' demands are becoming more sophisticated, it is becoming increasingly difficult for network administrators to maintain a network day and night so that the network continues to provide reliable and high-quality services. It is also becoming increasingly desirable to manage a network not reactively but proactively.
Under these circumstances, it is becoming important to collect a lot of information on the current state of a network (e.g., what device exists in a network and what its setting and operating conditions are, at what level the network performance is and where the problem is now, or the like). This is because, if an administrator can know the current network status in detail, it becomes possible to optimize the network by changing the configuration, adding or replacing devices, or the like, and it also becomes possible not just to detect and handle a network fault at an early stage but also to anticipate a fault and prevent a future problem.
Network management includes, for example, fault management, performance management, configuration and change management, accounting management, and security management. A known example of a tool for doing such network management is “HP OpenView Network Node Manager” provided by Hewlett-Packard Japan, Ltd. (see its corresponding English version: “HP OpenView Network Node Manager; Managing Your Network with HP OpenView Network Node Manager,” July, 2004, http://ovweb.external.hp.com/ovnsmdps/pdf/t2490-90024.pdf).
Fault management is to detect, isolate, and control faults in a network, and requires a tool for monitoring the current state of the network and activating an alarm. Performance management is to measure the performance of network hardware, software, and media, such as throughput rate, percentage utilization, error rates, and response time, through the collection and analysis of data about the network. Configuration and change management is to find and set up devices that control the behavior of a network, and the setting can be done by central control. Accounting management is to acquire statistical information on network use (e.g., resource consumption). Security management is to protect a network and its interconnections, systems, and network management information from unauthorized access and use.
The HP tool can display a network topology map. Using a protocol called SNMP (Simple Network Management Protocol) that works on TCP/IP, IPX, UDP, or other communications protocols, the tool can acquire data from devices in a network and inform, on the above map, a network administrator of an alarm based on the acquired data.
SNMP is implemented via an SNMP manager program installed on a network management station and via an SNMP agent program being resident in a required node in a network. This allows two ways for the network management station to collect above data for monitoring. One method is that the SNMP manager acquires data by polling, which is responded by each SNMP agent. The other method is that the SNMP manager acquires data by receiving a trap (notification) from an SNMP agent without sending an explicit request.
In order to manage a network as described above, data, which may change every moment, are acquired from devices in the network at a frequency appropriate for the management, and each element (e.g., node, link) in the network is monitored based on the acquired data. That is, the current state of each element is found out.